“In relation to the postal vote, the usual arrangements in relation to campaign materials under the Electoral Act will not be in play as it is being conducted by the Australian Bureau of Statistics as a household survey,” Ms O’Byrne said.

“Posters in yards and on property are a matter for local governments but signs placed on power poles – because they are the property of the State Government – are potentially illegal.

“Now that signs have already been erected, Mr Groom and the Department of State Growth should be investigating and – if they are found to be illegal – they should be removed.

“This is already a highly emotive issue which is likely to see passionate debate throughout the community and the Liberal Government should not be allowing government-owned assets to be used as part of that debate.”